This invention relates to a composite part that is made partially of a thermoplastic material and intended specifically, but not exclusively, for automobiles.
The automotive industry is an industry that assembles different parts to build a vehicle. The assembly costs form a significant part of the total cost of a vehicle despite the progress that has been made, in particular through robotics.
Most of the assembled parts are metallic. However, with respect to the interior trim, textile-covered plastic materials are becoming more common.
A number of parts used for the interior trim in vehicles are semi-rigid parts. They are made from relatively flexible materials such as the following textiles: moquette, baize, leather, thin films etc. It is common to stiffen these products partially by applying additives or appropriate treatments, and then molding them by thermoforming or cold forming in a press. Such parts must be adequately fastened to parts of the metallic or other structures of the vehicle body.
Currently, such parts are affixed using housings attached to the semi-rigid part. Attaching the housing requires a precise and expensive reworking process. Fasteners or clips are then mounted in the said housings and allow the part to be attached to the car body.
A first purpose of this invention is to solve this drawback and to make it possible to rigidify a semi-rigid part.
A second purpose of this invention is to obtain fastenings such as housings that are integrated with the semi-rigid part during molding and positioned appropriately.
According to the invention, the composite part comprised of a semi-rigid material has a rigid over-molding around its edges. The molded semi-rigid part is introduced into a thermoplastic injection mold so that the edges can be over-molded. This process results in a rigid plastic flange that makes it easy to handle the entire part. Another characteristic of the invention is that the rigid edge strip contains appropriately placed fastenings. These fastenings can consist of small housings to which fasteners are added, or simply of integrated clips. Thus all the attachment points are integrated into a single over-molding process with the same degree of precision that would be obtained if the entire part were made of a thermoplastic. The part can be clipped directly on to the car body, resulting in considerable time savings.
According to a specific production method of the invention, a flexible plastic area is integrated into the rigid strip. This flexible area in the rigid strip can ensure a seal where sensitive areas of the car body are involved and help to soundproof the passenger compartment.